Securities Exchange Agreement and Plan of Exchange BETWEEN Diatom Corporation AND Solar Energy Limited AND Planktos, Inc. DATED January 12, 2007

Solar and Planktos. Solar and Planktos, jointly and severally, make the representations and warranties set out hereto to Diatom, recognizing that Diatom is relying on such representations and warranties in entering into the transactions contemplated by this Agreement. All due diligence searches, investigations or inspections by Diatom, up to the Closing, are without prejudice to Diatom’s right to rely upon the representations and warranties of Solar and Planktos in entering into the transactions contemplated by this Agreement.

Incorporation and Qualification. Planktos is duly incorporated, organized and validly subsisting under the laws of the State of California. Planktos has all requisite corporate power and authority to own, lease, and operate its respective properties. Planktos is duly registered, licensed or qualified to carry on the Business in the jurisdictions in which the nature of the business as now being conducted by it or the property owned or leased by it makes such registration, licensing or qualification necessary.

Authority, Filings, Consents and Approvals. Solar and Planktos have the corporate power and authority to enter into this Agreement and to perform the transactions contemplated by this Agreement. This Agreement has been duly authorized, executed and delivered by Solar and Planktos and constitutes a legal, valid and binding obligation of Solar and Planktos, enforceable in accordance with its terms, subject to bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and similar laws of general applicability relating to or affecting creditors’ rights and to general equity principles. No other proceedings on the part of Solar or Planktos are necessary to authorize the entering into of this Agreement and the consummation of the transactions contemplated hereby. The execution, delivery and performance of this Agreement and the agreements contemplated herein will not require Solar or Planktos, to obtain any consent, waiver, authorization or approval of, or make any filing with or give notice to, any person, except for such consents, waivers, authorizations or approvals which the failure to obtain would not be reasonably likely to have a material adverse effect on the Business.

Capitalization of Planktos. The authorized capital of Planktos consists of 10,000,000 shares of no par value common stock, of which only the Planktos Shares are issued and outstanding. The Planktos Shares are duly authorized, validly issued, fully paid and non-assessable and are owned of record and beneficially by Solar, free and clear of any and all Encumbrances.

Corporate Records. All transactions of Planktos have been promptly and properly recorded or filed in or with its respective books and records, and the minute books contain complete and accurate records of the meetings and proceedings of shareholders and directors thereof.

Planktos’ Directors. ▇▇▇▇ ▇▇▇▇▇▇ is the sole director and officer of Planktos.

The Planktos Shares. Solar has good and valid title to the Planktos Shares, free and clear of all Encumbrances. There are no outstanding options, warrants or rights to purchase or acquire, or securities convertible into or exchangeable for or which carry an obligation to purchase or otherwise acquire, any shares or securities in the capital of Planktos and there are no other contracts, commitments, agreements, understandings, arrangements or restrictions which require Planktos to issue, sell or deliver any of its respective shares or securities and there are no restrictions on the transfer of the Planktos Shares.

Liabilities. Except as shown in its most recent audited financial statements (the “Planktos Financials”), attached as Exhibit B hereto, Planktos has no material liabilities of any kind whatsoever, contingent or non-contingent, other than those incurred in the ordinary course of business, including, without limitation, commercial real estate leases, utilities, telephone, and legal services.

Liabilities at Closing. Except as may otherwise be set forth in Section 3.1.7 above, the value of all liabilities of Planktos, including any exposure under any guarantees, as at the Closing will be zero.

Assets. Planktos has good and marketable, legal and beneficial title to all of the property comprising its assets as shown on the Planktos Financials, free and clear of all Encumbrances. Such assets constitute all of the property, rights and other assets used by Planktos, or which are necessary or desirable to conduct Planktos’ business as conducted prior to the date hereof. Without limiting the generality of the foregoing, none of the personal property or the fixed plant and equipment shown in the Planktos Financials is leased or otherwise used in Planktos’ business subject to any agreement with any third party.

Corporate Records and Financial Statements. All material transactions relating to the Business have been promptly and properly recorded or filed in or with Planktos’ books and records. The Planktos Financials fairly and accurately represent the financial condition and position of the Business as at such date. Solar will furnish to Diatom copies of the Planktos Financials, including the audited balance sheets of Planktos and the audited statements of income, changes in shareholders’ equity and statements of cash flow for the periods ended December 31, 2005 and December 31, 2006, together with the notes thereon and the report of its independent certified public accountants. The audited financial statements (i) have been or will be prepared in conformity with United States generally accepted accounting principles applied on a consistent basis from year to year (except as noted otherwise therein), and (ii) assuming Planktos will continue as a going concern, are true and correct and present fairly in all material respects the financial condition of Planktos and the results of operations and changes in cash flow of Planktos for the periods to which each relates.

Environmental Compliance. Except in compliance with Environmental Laws, Planktos has not caused or permitted, and Planktos and Solar have no knowledge of, any material release or disposal by any person of any Hazardous Substance on or from any premises formerly or presently used in the Business. All Hazardous Substances generated, handled, stored, treated, processed, transported or disposed of in the course of the Business have been generated, handled, stored, treated, processed, transported or disposed of in all material respects, in compliance with applicable Environmental Laws and the Environmental Permits.

Intellectual Property Rights. Exhibit A sets forth a true and complete list of all patents and trademarks (“Intellectual Property Rights”), registered or unregistered, owned by or licensed to Planktos and used in the Business. The Intellectual Property Rights, and Planktos’ trade secrets and know how, constitute all of the intellectual property necessary to process, market and sell the products of the Business in the manner presently conducted by Planktos. Planktos does not use any trademarks or patents other than those listed in Exhibit A, nor does it use any other intellectual property of any third party that it is not licensed or otherwise entitled to use. All registrations with respect to Intellectual Property are valid, current and in good standing.

Payment of Taxes. Planktos has paid all Taxes due and payable in relation to the Business and has paid all assessments that Planktos has received in respect of Taxes.

Reassessments. No reassessments of Taxes have been issued against Planktos in relation to the Business nor is Planktos aware of any pending or threatened assessment or reassessment for Taxes. Planktos has not executed or filed with any Governmental Authority any agreement extending the period for assessment, reassessment or collection of any Taxes.

Withholdings. Planktos has withheld from each payment made to any of the employees of the Business or former employees, officers and directors, and to all other persons, all amounts required by law and will continue to do so until the Closing and has remitted or will remit, such withheld amounts within the prescribed periods to the appropriate Governmental Authority. Planktos has charged and collected and have remitted or will remit on a timely basis all Taxes as required by Applicable Law on any sale, supply or delivery whatsoever, made in relation to the Business.

Contracts. Planktos is not a party to, or bound by, any material contract, agreement or commitment of any kind in relation to the Business other than this Agreement and the Material Contracts. The Material Contracts are in full force and effect. There is not any pending or threatened cancellation, existing default, or event under any of the Material Contracts which, after notice or lapse of time, or both, would constitute a default under any of the Material Contracts and all of the Material Contracts are terminable on reasonable notice as required by Applicable Law if termination of any of the Material Contracts is not expressly provided for in any of the Material Contracts, or sixty (60) days’ notice or less if termination of any of the Material Contracts is expressly provided for in any of the Material Contracts.

Employees. Complete and accurate particulars of the Employees pertaining to the date of hire of such employees and their annual remuneration and the names of those on long term disability, workers’ compensation or leave of absence (if any) will be provided to Diatom upon request. Planktos does not have any written employment agreements relating to any of the Employees, except that Employment Agreement with ▇▇▇▇ ▇▇▇▇▇▇.

Collective/Employment Agreements. None of the Employees is employed under a contract which cannot be terminated by Planktos, with or without notice, including those employees who are employed on indefinite hirings requiring reasonable notice of termination by Applicable Law. Planktos is not a party, either directly or by operation of law, to any collective agreement. No trade union, council of trade unions, employee bargaining agency or affiliated bargaining agent holds bargaining rights with respect to any of the employees of the Business by way of certification, interim certification, voluntary recognition, or successor rights. There are no threatened or pending union organizing activities involving the Employees and there are no threatened labor disputes or work stoppages relating to, or connected with, the Business.

Occupational Health and Safety. There are no outstanding inspection orders or charges or any other Orders made against Planktos or the Business. Planktos is in compliance with all occupational health and safety rules and regulations in all material respects in relation to the Business and there are no outstanding violations of such rules and regulations.

Insurance. All insurance policies relating to the Business are in full force and effect and Planktos is not in default with respect to any of the provisions contained in any such insurance policy. Planktos is not aware of any events or occurrences that could reasonably form the basis for a claim under Planktos’ policies of insurance.

Permits. Planktos will own, possesses and will be in compliance with, all Permits required by any Governmental Authority and necessary to conduct the Business.

Absence of Legal Conflicts. The execution and delivery of this Agreement by Solar and Planktos does not, and the performance of this Agreement by such parties and the completion by them of the transactions contemplated by this Agreement will not:

conflict with or violate the constating documents of Planktos or Solar, or any resolution of the director or Planktos or the directors of Solar;

conflict with or violate any Applicable Law; or

result in any breach of or constitute a default (or an event which with notice or lapse of time or both would become a default) under, or give to others any rights of termination, amendment, acceleration or cancellation of, or result in the creation of an Encumbrance on any of Assets pursuant to, any note, bond, mortgage, indenture, contract, agreement, lease, license, permit, franchise or other instrument or obligation to which Solar or Planktos is a party in relation to the Business or by which the Business or the Assets is bound or affected, which, in any such case, would prohibit or delay such Parties’ ability to perform their respective obligations under this Agreement.

Litigation. There are no claims, actions, proceedings, suits, investigations or reviews pending or threatened against Solar or Planktos or otherwise in relation to the Business or the Assets or the Planktos Shares, before or by any Governmental Authority.

Conduct of Business — Changes. Since December 31, 2006:

Planktos has conducted the Business in the ordinary course, using reasonable efforts to preserve the Business;

increased the compensation paid or payable to any of the Employees or increased the benefits to which the Employees are entitled or provided any new benefits for any such employees; or

modified, amended or terminated any contract to which it is or was a party in relation to the Business, except in the ordinary course of business with a view to the best interests of the Business.

Copies of Documents etc. True and complete copies of the documents and agreements listed in the Exhibits hereto which are in writing have been made available to Diatom and its counsel for review.

Diatom. Diatom makes the representations and warranties set out hereto to Solar and Planktos, recognizing that Solar and Planktos are relying on such representations and warranties in entering into the transactions contemplated by this Agreement. All due diligence searches, investigations or inspections by Solar and Planktos, up to the Closing, are without prejudice to Solar’s and Planktos’ right to rely upon the representations and warranties of Diatom in entering into the transactions contemplated by this Agreement.

Incorporation and Qualification. Diatom is a corporation duly organized, validly existing and in good standing under the laws of the State of Nevada and is duly qualified as a foreign corporation in all jurisdictions in which the failure to so qualify would have a material adverse effect on Diatom.

Authority, Filings, Consents and Approvals. Diatom has the corporate power and authority to enter into this Agreement and to perform the transactions contemplated by this Agreement subject to shareholder approval and the filing of pertinent disclosure filings with the Commission. This Agreement has been duly authorized, executed and delivered by Diatom and, subject to shareholder approval, constitutes a legal, valid and binding obligation of Diatom, enforceable in accordance with its terms, subject to bankruptcy, insolvency, fraudulent transfer, reorganization, moratorium and similar laws of general applicability relating to or affecting creditors’ rights and to general equity principles. No other proceedings on the part of Diatom are necessary to authorize the entering into of this Agreement and the consummation of the transactions contemplated hereby. The execution, delivery and performance of this Agreement and the agreements contemplated herein will not require Diatom to obtain any consent, waiver, authorization or approval of, or make any filing with or give notice to, any person, except for any such consents, waivers, authorizations or approvals which relate to shareholder approval and disclosure filings with the Commission.

Solar’s and Planktos’ Deliveries at Closing. At the Closing or as soon as practicable thereafter, Solar and Planktos will deliver to Diatom the following:

    4.1.1.        Share certificates representing the Planktos Shares, duly endorsed for transfer to Diatom, to be delivered to Diatom at Closing;

A certified copy of the resolution of the board of directors of Solar authorizing the execution and delivery of this Agreement and all documents to be executed and delivered by Solar at Closing.

Any consents required to transfer the Planktos Shares to Diatom;

All discharges and notices of discharge, estoppel letters, pay-out letters or similar discharging documentation, in registrable form if required, which are necessary or desirable to effect or evince the discharge of any Encumbrances, all of which are satisfactory in form and content to Diatom, acting reasonably;

A certificate jointly signed by an officer of Solar and officer of Planktos, certifying that at and as of the Closing Date, the representations and warranties contained in this Agreement are true and correct as if made at the Closing Date and that all covenants, agreements and conditions required by this Agreement to be performed or complied with by Planktos or Solar prior to or at the Closing Date have been performed and complied with; and

Such other documents, certificates, instruments and agreements as are required or contemplated to be delivered by Planktos or Solar pursuant to this Agreement.

the purchase of the Planktos Shares by Diatom;

the execution and delivery of this Agreement and all documents to be executed and delivered by Diatom at Closing;

the appointment by Solar, at its option, to nominate up to 3 of the 5 proposed directors of Diatom.

A certificate of an officer of Diatom, dated as of the Closing Date, certifying on behalf of Diatom that at and as of the Closing Date the representations and warranties of Diatom contained in this Agreement are true and correct as if made at the Closing Date and that all covenants, agreements and conditions required by this Agreement to be performed or complied with by Diatom prior to or at the Closing Date have been performed and complied with, except as otherwise specifically disclosed to Solar by notice in writing; and

Such other documents, certificates, instruments and agreements as are required or contemplated to be delivered by Diatom pursuant to this Agreement.

Conditions Precedent to Obligations of Diatom. The obligations of Diatom under this Agreement to consummate the Closing contemplated hereby will be subject to the satisfaction on or before the Closing Date, of the following conditions, provided, however, that Diatom may waive the pre-Closing performance of the following conditions (as conclusively established by Closing) without waiving its right to require the post-Closing performance of the following conditions (unless expressly waived in a signed writing):

Representations and Warranties True. The representations and warranties of Solar and Planktos will be in all material respects true and accurate as of the date when made, and, except as to representations and warranties which are expressly limited to a state of facts existing at a time prior to the Closing, will be in all material respects true and accurate at and as of the Closing Date.

Performance of Covenants. Solar and Planktos will have performed and complied in all material respects with each and every covenant, agreement and condition required by this Agreement to be performed or complied with by it prior to or as of the Closing Date.

No Governmental or Other Proceeding or Litigation. No order of any court or administrative agency will be in effect which restrains or prohibits any transaction contemplated hereby; and no suit, action, other than the exercise of dissenters’ rights, investigation, inquiry or proceeding by any governmental body or other person or entity will be pending or threatened against Planktos which challenges the validity or legality, or seeks to restrain the consummation, of the transactions contemplated hereby.

Business Plan. Solar and Planktos will have provided to Diatom a twelve (12) month budget and business plan satisfactory to Diatom.

Closing Documentation. Diatom will have received the documents identified in Section 4.1 and such additional documentation at the Closing Date as Diatom and its counsel may reasonably require to evidence compliance by Solar and Planktos with all of their obligations under this Agreement.

Representations and Warranties True. The representations and warranties of Diatom will be in all material respects true and accurate as of the date when made, and, except as to representations and warranties which are expressly limited to a state of facts existing at a time prior to the Closing, will be in all material respects true and accurate at and as of the Closing Date.

Performance of Covenants. Diatom will have performed and complied in all material respects with each and every covenant, agreement and condition required by this Agreement to be performed or complied with by it prior to or as of the Closing Date, including but not limited to, the condition that as of the Closing Date Diatom will have a minimum of one million U.S. dollars ($1,000,000) in working capital available for the implementation of Planktos’ twelve (12) month budget and business plan minus any amounts already spent by Diatom on the Business either directly or indirectly in the form of loans to Planktos.

No Governmental or Other Proceeding or Litigation. No order of any court or administrative agency will be in effect which restrains or prohibits any transaction contemplated hereby; and no suit, action, other than the exercise of dissenters’ rights, investigation, inquiry or proceeding by any governmental body or other person or entity will be pending or threatened against Diatom which challenges the validity or legality, or seeks to restrain the consummation, of the transactions contemplated hereby.

Share Cancellation. Diatom will have cancelled and returned to authorized share capital thirty million (30,000,000) common shares of those Outstanding Shares described in this Agreement.

Closing Documentation. Solar and Planktos will have received the documents identified in Section 4.2 and such additional documentation at the Closing as Solar and Planktos and their respective counsel may reasonably require to evidence compliance by Diatom with all of its obligations under this Agreement.